Question

1. there are 7.0 × 10^6 red blood cells (rbcs) in 1.0 mm^3 of blood. how many red blood cells are in 1.0 l of blood?

Explanation:

Step1: Convert liters to cubic - millimeters

We know that $1\ L = 1000\ cm^{3}$ and $1\ cm^{3}=1000\ mm^{3}$, so $1\ L=(1000\times1000)\ mm^{3}= 10^{6}\ mm^{3}$.

Step2: Calculate the number of RBCs

If there are $7.0\times 10^{6}$ RBCs in $1.0\ mm^{3}$ of blood, then in $1.0\ L = 10^{6}\ mm^{3}$ of blood, the number of RBCs is $(7.0\times 10^{6})\times10^{6}$. Using the rule of exponents $a^{m}\times a^{n}=a^{m + n}$, we have $(7.0\times 10^{6})\times10^{6}=7.0\times10^{6 + 6}=7.0\times 10^{12}$.

Answer:

$7.0\times 10^{12}$